# A126391 (b-file synthesized from sequence entry) 1 1 2 1 3 4 4 24 5 240 6 4320 7 146880 8 9694080 9 1260230400 10 325139443200 11 167121673804800 12 171466837323724800 13 351507016513635840000 14 1440475753672879672320000 15 11803258325595576034990080000